.. _nustar_dcs_deployment:

Deployment
==========

In order to maintain control over a group of devices in a consistent state, NUSTAR DCS suggests common rules and procedures for deployment of EPICS IOCs on these devices.

.. note:: This is a work in progress.

Raspberry Pi
------------

All Raspberry Pi computers used in NUSTAR DCS should run the *epicsian* image provided by NUSTAR DCS. This image is generated using the standard `pi-gen framework <https://github.com/RPi-Distro/pi-gen>`_ used to produce the official raspberrypi.org Raspbian images. The *epicsian* image installs Raspbian-lite on the SD-card and includes the EPICS base system including all required modules for the IOCs.

The current image can be found in this location::

  lx-pool.gsi.de:/u/land/epics_stuff/images/

Two images are provided:

+ :file:`image_<date>-epicsian-modules.zip`: Only EPICS base + modules
+ :file:`image_<date>-epicsian-ioc.zip`: EPICS base + modules + IOCs

In the future, more images with additional functionality may be provided. These images can be used on *any* Raspberry Pi computer available so far.

.. rubric:: Pi-gen build process

Check out the pi-gen epicsian git repository::

  git clone lx-pool.gsi.de:/u/bloeher/git-bare/epics/pi-gen.git
  cd pi-gen

and change to the *epics* branch::

  git checkout -b epics origin/epics

To build the *epicsian* image, a few prerequisites are required. These are detailed in the :file:`README.md` included in the repository.

Configure the build by writing the config file::

  echo "IMG_NAME=epicsian" > config

Then run the :file:`start.sh` script (at best from within a multiplexed terminal session). This will start a docker container that runs the complete build process and takes approximately 1-2 hours. Upon successful completion, the zipped images can be found in a new directory :file:`deploy`.